A DIN rail, sometimes referred to as a top-hat rail, is a standardized elongated channel rail having laterally spaced oppositely projecting abutment flanges that gives it a cross-section having a hat-shaped appearance. DIN rails are widely used for mounting circuit breakers inside equipment racks, particularly in Europe.
Prior art DIN rail mountable circuit breakers generally fall into one of two categories. In the first, the circuit breakers have a fixed opening, requiring they be mounted onto the rail at one of the rail's ends and slid along the rail into position. In the second, the circuit breakers have a variable opening for clamping over the rail. Embodiments which are only slidable face the disadvantage that if the circuit breaker needs to be replaced, significant amounts of work can be involved in disconnecting and/or removing adjacent breakers and other items until the faulty breaker can be slid entirely off of the rail. Current versions of embodiments that employ a clamping mechanism are subject to overstressing, which can result in breaking the circuit breaker.
These and other drawbacks are found in current DIN rail mountable circuit breakers.